Reciprocating engine.



PATENTED JUN :19.04.

T. H. PHILLIPS. I

REGIPROGATING ENGINE.

` Arrmourou FILED 11.150,22, 1902. '4 SHEETS-SHEET 1.

No MODEL.

s ...u mw Q. Q QQ PATENTED JUNE 14, 1904'.

T. H. PHILLIPS.

REGIPROCATING ENGINE. y

APPLICATION FILED DEO. Z2, 190%` 4 SHEETS-SHEET 2v.

BO MODEL.

NN S N w: Nonms mince. Prgaroumo.. wAsHmmN D c l110.761).,755., PATBNTBDJUNE 14, 1904.

.y T. H.PH1LL1Ps.

RBGIPROGATING' ENGINE'. uruonmu num nso. zz, 1902. No MODEL 4SHEETS-SHEET a.

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` PATENTED JUNE ,14, 1904. T. H. PHILLIPS. RECIPROGATING ENGINE.APrLIoATIN FILED DB0. 22, 1902.

4 SHEETS-SEEBT 4';

N0 MODEL.

Patented June 14, 1904.

PATENT OFFICE.

THOMAS H. PHILLIPS, OF ST. DAVIDS, PENNSYLVANIA# RECIPROCATING ENGINE.

SPECIFICATION forming part of Letters Patent No. 762,755, dated June 14;1904.

Application filed December 22. 1902.. Serial No. 136,192. (No model.) i

To all whom, it may concern,.-

Be it known that I, THOMAS H. PHILLIPS, a citizen of the United States,residing in St. Davids, Delaware county, Pennsylvania, have inventedcertain Improvements in Reciprocating Engines, of which the following isa speciication.

My invention relates to that class of reciprocating engines in which arecombined a cylinder having a reciprocating piston or plunger and avalve-chest having a reciprocating valve, both piston and valve beingmoved by direct action of the steam,`air, or other motive fluidemployed. One type of engine of this class is an impact-tool, such asarockdrill, and another type is a `directacting pump. For convenience Iwill assume that it is an engine of the formerclass and is operated bysteam.

The objects of my invention are to vprovide a simple and positive methodof moving the valve at ak predeterminedl point in the stroke ofthepiston, to provide an engine that with the same power and efficiency ascompared with others of the same length of stroke is lighter and moreeasily handled, and to maintain the full length of stroke of the piston.regardless of any wear that may take place on the piston or in thecylinder. These objects I attain in the manner hereinafter set forth,reference being had to the accompanying drawings,in which- Figure 1 is alongitudinalsection of the cyl` inder and valve-chest of a reciprocatingen gine constructed in accordance with my invention, showing the pistonand valve in elevation and at the forward extremes of their movement.Fig. 2 is a longitudinal 'section looking in the opposite direction andshowing the piston and valve at the rearward eX- treme of theirmovement. Fig. 3 is a sectional plan on the line a a, Fig. 1.y Fig. 4 isa sectional plan on the line b, Fig. 1; and

Fig. 5`is a longitudinal 'section illustrating the application of myinvention to an engine having a short piston.

In the drawings I have shown simply the cylinder and valve-cheststructure, the piston,

`and the valve, omitting the heads'of the cylinder and all otherappurtenances not necessary to the proper understanding of my invention.1 represents the cylinder, and 2 the piston contained therein, thelatter beingasolidpiston-that is to say, a piston not having any centralgroove-'and being provided with packing-.rings 3 3, one near eachend,tlie piston shown vin Fig. 1 being a long piston of the type usuallyemployed in connection with rock-drills or like impact-tools. y

The valve-chest is represented at 4 and is suitablymounted upon thecylinder, said' valve-chest having a steam-chamber 5 with oppositeopenings, either of which may be connected to the supply-pipe, the otherbeing suitably plugged, thus permitting the tool to receive steam from apipe either on the righthand side or on the left-hand side of the same,as may be found most convenient in practice. In the top of the chest isanother opening 6, which constitutes the exhaust-opening and is intendedto receive a pipe for conveying the exhaust to any desired point, or itmay diswhich communicates with a chamber 14 of the valve-chest.

The bore of the valve-chest at a point between the chamber 7 and theforward end of the chest is in communication with a chamber 15, whichconstitutes the valve-chest termination of a passage 15, and at a pointbetween the passage 8 and the' rear end of the valvechest the bore ofthe latter isk in communication with a chamber 16, which constitutes thevalve-chest termination of a passage 16E.

The passage 15 is for convenience in construction formed partly in thevalve-chest and IOC partly in the cylinder instead of being formedentirely in the cylinder, and it communicates with the bore of thecylinder through two ports 15b and 15C at one side of the cylinder, theport 15b being located some distance inwardly from the forwardk end ofthe cylinder and the port 15c being located some distance in advance ofthe rear end of the cylinder.

The passage 16a resembles the passage 15a and like it communicates withthe bore of the cylinder through a forward port 16b and a rear port 16C,the port 16b being some distance in advance of the port 15b and the port16c being some distance in advance of the port 15, the ports 16b and 16Cbeing on the opposite side of the cylinder from the ports 15b and 15C,as shown in Fig. 4, so that the two sets of passages will not interferewith each other.

The valve has five disks 17 18, 19, 20, and 21, the disk 17 beingcentrally disposed on the valve-stem, the disks 18 and 19 being at theforward end of the stem, and the disks 20 and 2 rlhe i tinues to moverearwardly its rear endcovers the port'lc, thereby cutting of thepassage 15 from communication with the exhaust, and l still furtherrearward movement of the piston Icauses its forward end to uncover theport end disks 18 19 and 2O 21 may be of the same 15", therebypermitting flow of live steam from the forward end of the cylinder intothe f passage 15a and thence through the chamber j 15 and the passage 24of the valve into the 1 forward end of the valve-chest. i the forwardend of the disk 19 is now added i to the excess annular area of the disk17 over I that of the disk 18 in exerting pressure to move 21 being atthe rear end of the same. end disks 18 and 19 and 2O and 21 areseparated from each other by narrow grooves, and the disks 18 and 20 areseparatedfrom the central disk 17 by wider grooves.v

In the case of a steam-pump the pairs of diameter, as in such caseuniform forward and backward movement of the valve is required; but inthe case of a rock-drill or other impacttool it is preferable that theforward pair of disks 18 and 19 shall be of somewhat greater diameterthan the rear disks 2() 21 in order that the valve may have a quickerrearward than forward movement. The central disk 17 is of greater areathan the end disks, the difference in area between said central diskandV either end disk being less than the area of the opposite end disk.For convenience of manufacture and in order to insure accuracy inalinement the valve-chest is in the rst instance bored out to the fulldiameter of the disk 17, and the desired reduction indiamcter of bore atthe ends of the chest is effected' by the insertion of bushings 22 and23.

In the stem of the -valve at the forward end of the same is formed apassage 24, branched at its inner end, so as to communicate with thegroove between the valve-disks 18 and 19, and a similar passage 25 atthe rear end of the stem communicates with the groove between thevalve-disks 20 and 21.

Supposing that the piston and valve are at the forward ends of theirrespective strokes, as shown in Fig. 1, the operation of the engine isas follows: The forward end of the cylinder is open to the steam-inletchamber 7 through the passage 11, chamber 12, and the groove between thedisks 17 and 18 of the valve, and the rear end of the cylinder is opento the exhaust-chamber 9 through the passage 13, chamber 14, and thegroove between the disks 17 and 20 of the valve. The rear end of thevalve-chest receives steam under pressure from the steam-passage 8through the passage 25, while the forward end of the steam-chest is opento the exhaust through the passage 24, the chamber 15, the passage 15a,the rear end of the cylinder, the passage 13, and the chamber 14. Therear face of the disk 18, the forward vface of the disk 17, the rearface of the disk 20, and the forward and rear faces of the disk 21 aretherefore subjected to steam-pressure. Hence the pressure to hold thevalve in the forward position is that exerted upon the rear face of thedisk 21 as against the backward pressure exerted upon that portion ofthe forward face of the disk 17 which is in excess of the area of therear face of the disk 18. As the piston moves .rearwardly in thecylinder its rear end first covers the port 16, and its forward end thenuncovers the port 16"; but as the valve-chest end of the passage 16.iscovered bythe disk 21 of the valve this has no effect upon the movementof the valve. As the piston con- The area of the valve rearwardly, andas this-pressure is in excess of the pressure lexerted upon the reardisk 21 of the valve said valve will be at once moved to the positionshown in Fig. 2, thereby admitting steam to the rear end of the IOOcylinder to cushion the piston on the back stroke and at the sametimeopening the front end of the cylinder to the exhaust, and consequentlypermitting the exhaust of steam from the rear end of the valve-chestthrough the passage 25, the chamber 16, passage 16, the front end of thecylinder, the passage 11, and the chamber 12. The disk 20 of the valveis wider than the chamber 8 or the space between the same and thechamber 16 or the groove between the disks 2O and 21, and in like mannerthe disk 18 is wider than the chamber 7 or the space between the sameand the chamber 15 or the groove between the disks 18 and 19, and thedisk 17 is narrower than the chamber 9. By reason of this constructionthe chamber 16 will in the backward movement of the valve be uncoveredby the disk 21 before the disk 20 permits passage of live steam from thechamber 8 to the rear end of the cylinder through the kpassage 13 orsubjects the rear face of the disk 17 to such live-steam pressure. Atthe time that the disk 21 uncovers the chamber 16 the disk 17 beginstouncover theexhaust-chamber 9. Hence there is free exhaust of steam fromthe rear end of the valve-chest through the passage 25, chamber 16,passage 16, the front end of the cylinder, the passage 11, and thechamber 12, and there is no risk ofaccidental reversal of the positionof the valve before the piston has completed its designed stroke. n

The purpose of making the disk 17 of less width than the exhaust-chamber9 is to prevent pressure upon either face of said disk by steam leakingaround the end disk which is in advance in the direction of movement ofthe valve and before said valve has moved so far that said end diskbegins to uncover the steam-inlet chamber, as such leakage would in casethe exhaust-chamber had been closed by the disk 17 exert such backpressure upon the latter as would render uncertain or actually preventthe desired movement of the valve. The piston now moves forwardly, firstcovering the port 15b and then uncovering the port 15C, which, however,has no effect upon the movement of the valve, owing to the fact that thevalve-chest end of the passage 15L is closed by the forward disk 19 ofthe valve. The port 16" is next closed by the forward end of the piston,so as to cut off the passage 165 from communication with the exhaust,and, finally, the port 16 is uncovered by the rear end of the piston, soas to admit steam to the rear end of the valve-chest through the passage16, chamber 16, and passage 25. The forward pressure upon the valve-disk21 inaddition tothe forward pressure upon the central disk 17 overcomesthe pressure upon the forward disk 19 of the valve and causes forwardmovement of the latter in the valvechest to the position shown in Fig.1, the exhaust from the forward end of the valve-chest taking placebefore theforward face of the disk 17 is exposed to the live-steampressure from the chamber 7. When the piston of the engine is short, asin the case of a pump, the ports 15"'.16b and 15C 16c are disposedclosely to the center of the cylinder to compensate for this differencein the length of the piston, as shown in Fig. 5. K

1t will be observed that the valve is moved in each direction by fullpressure upon one end disk, resisted by full pressure upon the other enddisk, the pressure upon the central disk 17 being the dominating factor.Hence the valve will be moved positively in each direction, even thoughthe end disks of the valve are of the same diameter. When the valvereaches its final position in the chest at either end, it is held inthat position by full pressure upon one end disk, the opposite end diskbeing free from pressure, this condition being maintained until thepiston has so far completed its stroke as to bring about the change inposition whereby the valve is shifted. The valve moves forwardly whenthe pistonv approaches the forward end of its stroke and backwardl'ywhen the piston 'apby steam direct from the rear end of the cylinder andrearwardly by steam from the front end of the cylinder and after themovement in either direction is held in place by steam fromthe maininlet-supply, and the chambers in the valve-chest for the admission ofsteam from either end of the cylinder to the corresponding end of thevalve -chest are never uncovered by either end of the valve, eachchamber being first in communication with the exhaust from the oppositeend of the cylinder, then receiving steam from the adjacent end of thecylinder to move the valve, and then being in communication with theexhaust from that end of the cylinder until the valve is again moved inthe reverse direction. v

When, as in some classes of rock-drills, a rifie-bar is used engagingwith the rear endA of the piston, said ypiston must be somewhat longerthan the length of the stroke, so as to prevent the rifle froml leavingthe piston when the latter is at the limit of its forward stroke. 1f,however, rotation of the piston is not required or is effected by spiralflutes on the piston-rod or by other means, the piston need be only longenough to accommodate packing` rings and provide sufiicient support oneach side of the same, the length of piston being independent of thelength of stroke. The

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two ports of either passage 15a or 16a should be so spaced vthat beforeone of the same is uncovered by one end of the piston for the admissionof pressure to move the valve the other will have been closed by theopposite end of the piston, so that only one port will be open topressure or exhaust on opposite sides of the piston at the same time,and there will be no accumulation of pressure back of the valve to causeits premature movement,

as any leakage which might take place be-` tween the cylinder andpacking-rings of the piston will escape through the exhaust from theopposite end of the cylinder until the piston covers the port on theexhaust' side.- While both ports of either passage 15a and 16 should notbe uncovered on opposite sides of the piston at the same time, they maybe open to either .pressure or exhaust on the same side of the pistonsimultaneously, as in`l the case of the engine with the short piston.k(Shown in Fig. 5'.)

Having thus described my invention,` I claim i and desire to secure byLetters Patentw` 1. The combination, ina reciprocating engine, of acylinder, a piston, a valve-chest, a valve having end disks withpassagestherethrough, passages leading from .thecylinder to thevalve-chest inwardly beyond the end inder-passages, whereby the valve ismoved in each direction in the valve-chest by motive iiuid admitted tothe end of the valvechest from the corresponding end of the cylinder andthrough the end disk of the valve and is retained in position in thevalve-chest by motive iiuid from the main'supply, substantially asspeciiied.

2. The combination, in a reciprocating engine, of a cylinder, a piston,a valvechest,and.

valve having end disks with passages therethrough, passages leading fromeach end portion of the cylinder to valve-chest chambers inwardly beyondthe end disks of the valve, and live-steam chambers in said valve-chestinwardly beyond said. cylinder chambers, whereby each end of thevalve-chest is first caused to communicate with the corresponding end ofthe cylinder through the end disk of the valve,l then with a mainmotive-fluid supply, and then with the exhaust through the opposite endof the cylinder, substantially as specified.

3. The combination, in a reciprocating engine, of a cylinder, a piston,a valve-chest, a valve having end disks, main motive-fluidsupplypassages, and passages communicating with the cylinder some distanceinwardly from the ends of the same, the end disks of the valve havingpassages therethrough, which, in one extreme position of the Valve,communicate with said cylinder-passage, and in the other extremeposition of the valve, communicate with the main motive-iiuid-supplypassage, substantially as specified.

4. rIhe combination, in a reciprocating engine, of a cylinder, a piston,a valve-chest, a valve having a forward end disk, with passagetherethrough, and a passage having branches terminating in front andrear ports in the cylinder, said passage having a valvechestport,which,when the valve is in its forwardextreme position,communicates, th rough the passage in the end disk of the valve, withtheforward end of the Valve-chest, substantially as specified.

5. The combination, in a reciprocating engine, of a cylinder, a piston,a valve-chest, a valve having a rear end disk with passage therein, anda'passage having branches terminating in front and rear ports in thecylinder, said passage having a valve-chest port, which, when the valveis in its cxtreme rear position, communicates, through the passage inthe end disk of the valve, with the rear end of the valve-chest,substantially as speciiied.

6. The combination, in a reciprocating engine, of a cylinder, a piston,a valve-chest, a valve having front and rear end disks each with passagetherethrough, two passages each having branches terminating in front andrear ports in the cylinder, one of said passages having a valve-chestport, which, when the valve is in its eXtreme forward position,communicates,through the passage in the forward end disk of the valve,with the forward end of the valve-chest, the other passage having, aValve-chest port, which, when the valve is in its extreme rear position,communicates, through the passage in the rear end disk of the Valve,with the rear end of the valve-chest, substantially as specified.

' 7 The within-described valve for a reciprocating engine, the samehaving pairs of disks at each end, with passages extending to each endof the valve from the grooves between the pair of disks at that end ofthe valve, and a single central disk of larger diameter than the enddisks, substantially as specified.

A8. The within-described valve for a reciprocating engine, said valvehaving a pair of disks at each end, the disks at one end being yofgreater diameter than vthose at the other,

and a single central disk of still greater diameter, substantially asspecified.

9. The within-described valve for a reciprocating engine, the samehaving at each end pairs of disks, those at one end being of greaterdiameter than those at the other, and each end of the valvecommunicating with the groove between the disks at that end,the valvealso having a single central disk of greater diameter than either of theend disks, substantially as specified.

10. The combination of the cylinder and its piston, a valve-chest, avalve having end disks and an intermediate disk of greater diameter thanthe end disk, said intermediate disk controlling the exhaust-chamber ofthe valvechest, and being of less width than said chamber, with passageswhereby movement of the valve in each direction is caused by pressureupon an end disk and upon the corresponding facle of the central disk,substantiall y as specifie In testimony whereof I have signed my name tothis specification in the presence of two subscribing witnesses.

THOMAS H. PHILLIPS.

Witnesses:

F. E. BEQHTOLD, Jos. H. KLEIN.

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